Nonetheless,SCM and CPS contain several inhibitory compounds that may affect the yeast cells metabolic activity which may reduce the process productivity. Indeed Takara et al., 2007 identified phenolic compounds in SCM that inhibited bacteria, and Lima et al., 2012 referred that the carob pulp aqueous extracts inhibited the growth of Pseudomonas putida, although no compounds were identified nor quantified.
Therefore,it is important to evaluate the yeast cell viability
when grown on these substrates.However,mostofthe works studying low-cost media formulations for carotenoid and lipid production by yeasts used traditional techniques for biomass quantification that do not give any information on the cell viability (Karatay et al., 2010; Kiran et al., 2013; Schneider et al., 2013).